Curcumin compounds have antioxidant properties and may be used in oral care compositions to exert beneficial physiological effects, such as prevention or amelioration of gingivitis or periodontitis. GB 2317339 discloses oral compositions for prevention and treatment of dental caries, periodontal diseases and other diseases of the oral cavity. The compositions include a curcuminoid and a fluoride ion source, in combination with oral care actives and carrier materials. SU 1,132,945 discloses incorporating extracts of turmeric or ginger into toothpaste compositions for improved anti-inflammatory effect on tissues of the oral cavity and treatment of certain diseases of the mucous membranes of the oral cavity and marginal periodontitis.
However, the incorporation of curcumin compounds into oral care compositions (such as toothpastes) presents problems. Degradation and unattractive discoloration have been observed on storage, especially at elevated temperatures.
The present inventors have found that the above problems can be solved by incorporating a source of zinc ions into the composition.